SCIENCE 



Editoeial Committee : S. Newcomb, Mathematics ; E. S. Woodward, Mechanics ; E. C. Pickeeing, 



Astronomy; T. C. Mendenhall, Physics; R. H. Thueston, Engineering; lEA Eemsen, Chemistry; 



J. Lb Contb, Geology; W. M. Davis, Physiography; O. C. Maesh, Paleontology; W. K. 



Beooks, C. Haet Meeeiam, Zoology; S. H. Scuddbe, Entomology; N. L. Beitton, 



Botany; Hbney F. Osboen, General Biology; H. P. Bowditch, Physiology; 



J. S. Billings, Hygiene ; J. McKeen Cattell, Psychology ; 



Daniel G. Beinton, J. W. Powell, Anthropology. 



Feidat, May 14, 1897. 



CONTENTS: 



On the Distribution of 3Iarine 3Iammals : P. L. 

 Sclatee 741 



Former Extetision of Cornell Glacier near the South- 

 ern End of 3Ielville Bay : T. C. Chambeelin ..748 



Suggestions for a New Method of Discriminating be- 

 tween Species and Subspecies : C. Haet Meeeiam. .753 



OJte National A cademy of Sciences : — 



On the Variation of Latitude ; The Variation of 

 Latitude at New York and a Determination of the 

 Constant of Aberration from Observations at the 

 Observatory of Columbia University ; Notes of Ex- 

 periments upon the Bontgen Rays 758 



The American Association for the Advancement of 

 Science: F. W. Putnam 760 



The Congress of American Physicians and Surgeons. .761 



Zoological Notes : — 



Color Change in the Plumage of Birds unaccom- 

 panied by Moud; F. A. LuCAS 762 



Notes on Inorganic Chemistry : J. L. H 763 



Astrophysical Notes : E. B. F 764 



Scientific Notes and News : — 



Legislation on the Forest Reservations; The Be- 

 quests of the late Professor Cope ; General 764 



University and Educational News 768 



IHseussion and Correspondence: — 



On Supposed Effects of Strain in Telescopic Objec- 

 tives : Alvan G. Clark. The Loess Formation 

 of the Mississippi Region : OscAE H. Heeshey.768 



Scientific Literature : — 



Ridgway on Birds of the Galapagos Archipelago : 

 C. H. M. Wiesbach and Hermann on the 3Iechanics 

 of Pumping Machinery : B. H. T 770 



Scientific Journals : — 



T/ie Journal of Comparative Neurology 773 



Societies and Academies : — 



Chemical Society of Washington : V. K. Ches- 

 NUT. Zoological Club of the University of Chi- 



cago : William Moeton Wheelee. The New 

 York Academy of Sciences : Subsection of Anthro- 

 pology and Psychology : LIVINGSTON Faeeand. 

 The St. Louis Academy of Sciences : William 

 Teelease 774 



New Books 776 



MSS. intended tor publication and books, etc., intended 

 for review sbould be sent to the responsible editor, Prof. J. 

 McKeen Cattell, Garrison-on-Hudson, N. Y. 



ON THE DISTRIBUTION OF 3IAEINE MAM- 



3IALS.* 



I. INTEODTJCTOKY EEMAEKS. 



Most of the recent writers on Geograph- 

 ical Distribution have confined their atten- 

 tion to terrestrial mammals, or, at any rate, 

 have but casually alluded to the marine 

 groups of that class. On the present occa- 

 sion I wish to call your attention to some 

 of the principal facts connected with the 

 distribution, over the world's surface, of the 

 marine, or aquatic, members of the class of 

 mammals. 



Aquatic mammals, which pass their lives 

 entirely, or, for the greater part, in the 

 water are, of course, subject to very dif- 

 ferent laws of distribution from those of 

 the terrestrial forms. As regards aquatic 

 mammals, land is, of course, an impassible 

 barrier to their extension, and, subject to 

 restrictions in certain cases, water offers 

 them a free passage. Just the opposite is 

 the case with the terrestrial mammals, to 

 which, in most cases, land offers a free pas- 



* Eead before the Zoological Society of London on 

 March 16th. 



